Apparatus for the formation of walled structures



Aug'. 22, 1967 H s. SMITH. JR 3,336,632 7 APPARATUS FOR THE FORMATION OF WALLED STRUCTURES Filed March 4. 1966 V 6 f mvamglz Hu er 6'. 6m! Jr.

Hubert S. Smith, J12,

United States Patent 3,336,632 APPARATUS FOR THE FORMATION OF WALLED STRUCTURES Bay City, Mich., assignor to The Dow Chemical Company, Midland, Mich., a corporation of Delaware Filed Mar. 4, 1966, Ser. No. 531,711 Claims. (Cl. 18-5) This invention relates to an improved apparatus for the formation of walled structures and more particularly relates to an improved walled structure from a liquid, hardenable, foam-forming composition.

Desirable structures are fabricated from synthetic resinous foamable materials as set forth in United States Letters Patent 3,206,899, wherein the strips of a plastic foam material are bonded to each other and spirally deposited to form a walled structure. US. 3,206,899 also discloses the preparation of such structure using particulate expandable granular plastic material which on expansion foams and forms a unitary body. Frequently, for many application-s such techniques are not desirable and it would be beneficial to prepare a walled structure from a liquid foamable, hardenable material deposited generally in the manner set forth in the Wright patent; however, considerable difiiculty is encountered in the restraining of the hardenable, foamable material in a channel having the desired rectangular configuration.

It would be desirable if there were available an apparatus for the preparation of walled structures by a spiral generation technique which would permit the use of a foamable, hardenable material.

It would also be advantageous if there were available a simplified foam depositing head which would deposit a foam strip of generally rectangular cross-sectional configuration from a foamable, hardenable substance.

It would also be advantageous if such an apparatus were available which would conform generally to the curvature of the structure being prepared.

These benefits and other advantages, in accordance with the present invention, are obtained in a foam depositing head for the spiral generation of walled structures, the foam depositing head comprising in cooperative combination a frame, the frame supporting a first pair of side rolls and a second pair of side rolls, the rolls being rotatably mounted in generally parallel relationship to each other, a first forming belt, the first forming belt having a first edge and a second edge, the first edge of the first forming belt defining a plurality of adjacent segments projecting outwardly therefrom and being in adjacent generally contiguous arrangement, the first edge of the first forming belt being disposed generally adajcent the frame, the first forming belt passing over the first pair of side rolls, a second forming belt passing over and being supported by the second set of side rolls, the second forming belt having a first edge and a second edge, the first edge of the second forming belt having a plurality of outwardly extending generally contiguous segments, the first and second forming belts defining therebetween a channel having three sides and a first end and a second end, the first and second ends of the channel being open, the first side being defined by the first forming belt, the second side being defined by the second forming belt and a third side defined by the segments of the first and second forming belts, means to rotate the first and second pairs of rolls and to move the adjacent surfaces of the first and second-forming belts in a like direction, means to provide a foamable, hardenable composition to the channel defined by the belts.

Further features and advantages of the present inven-.

tion will become more apparent from the following specification and drawing wherein:

the shaft 45. A

3,336,632 Patented Aug. 22, 1967 FIGURE 1 is a schematic ing belt and roll tion;

FIGURE 2 is a schematic end view of the apparatus in accordance with the invention; and

FIGURE 3 is a schematic representation of the support and drive mechanism for the roll configuration of FIGURE 1. g

In FIGURE 1 there is schematically depicted a forming configuration generally designated by the reference numeral 10. The forming configuration 10 comprises a first pair of rolls 11 and 12. The rolls 11 and 12 have shafts 13 and 14 about which they are rotated. A forming belt 16 passes about the periphery of the rolls 11 and 12. The belt 16 has a first edge 17 and a second edge 18. A plurality of dependent segments 20 project from the first edge 17 of the belt 16. The segments 20 project outwardly from the rolls 11 and 12. An outward tensioning roll 22 is disposed generally adjacent the roll 11 and is rotatble about a shaft 23. An inwardly tensioning roll 25 is disposed about midway between the rolls 11 and 12 and is rotatable about the shaft 26. Oppositely disposed and generally parallel to the rolls 12 and 13 are a second set of forming rolls 30 and 31. The rolls 30' and 31 have shafts 32 and 33, respectively. A second belt 35 passes about the periphery of rolls 30 and 31. The second forming belt 35 has a first edge 36 and a second edge 37. A plurality of contiguous segments 38 project outwardly from the upper edge 36 of the second belt 35. An outwardly tensioning roll 40 is disposed generally adjacent the roll 30 and is rotatably mounted upon the shaft 41. A second forming belt tensioning roll 43 is disposed within the loop formed by the belt 35 and is rotatable about dispenser 46 is disposed generally adjacent the rolls 11 and 30. The dispenser 46 is adapted to deliver a foamable, hardenable material to a channel, not shown, defined by forming belts 16 and 35 which form two sides of the channel. A third side of the channel is formed by the cooperation of the segments 20 and 38. A fisrt foam layer 47 is illustrated generally adjacent the dispenser 46 and a freshly formed walled layer 47a is shown generally adjacent the rolls 12 and 31. The forming apparatus moves in the direction indicated by the arrow.

In FIGURE 2 there is schematically illustrated a front view of a forming roll assembly generally as depicted in FIGURE 1 and designated by the reference numeral 50. The assembly 50 comprises in cooperative combination a frame 51. The frame 51 defines a support pivot 52. A support arm 53 is pivotally afiixed to the support 52 by means of a pivot pin 55. The frame 51 has affixed thereto a first bearing means 57. The bearing means 57 has journaled therein a shaft 58 secured in position by the set collars 59 and 60'. A roll 61 is rigidly atfixed to the shaft 58. A first forming belt 63 passes over the roll 61 and a second roll, such as the roll 12 of FIGURE 1, not shown. The forming belt 63 has a first edge 65 and a second edge 66. A plurality of segments 67 project outwardly from the first edge 65 of the belt 63. A second bearing 68 is rigidly supported adjacent the bearing 57. A shaft 69 is journaled within the bearing 68 and is generally parallel to the shaft 58. The shaft 69 is maintained in position by means of the set collars 70 and 71. A roll 72 is rigidly and coaXially aflixed to the shaft 69. A second forming belt 74 passes over the roll 72 and another roll such as the roll 33 of FIGURE 1. The belt 74 has a first edge 75 and a second edge 76. A plurality of segments 77 project outwardly from the first edge 75 of the belt 74. A foam dispensing head 78 is supported in a position generally adjacent the rolls 61 and 72 by means of support means 79. The belts 63 and 74 define a three sided channel 80. The channel 80 is bound on a representation of the formportion of the apparatus of the invenfirst side 81 by the belt 63, on a second side 82 by the belt 74, and on a third side 83 by the segments 67 and 77 which project from the belts 63 and 74. The foam dispenser 78 has a discharge end directed toward the channel 80. A motor 90 is operatively connected to a pulley 91 which drives a belt 92 which in turn engages a pulley 93 affixed to the shaft 58. A second pulley 94, affixed to the shaft 58, is in operative engagement with a belt 95 which engages a pulley 96 rigidly afiixed to the shaft 69 and provides positive drive to the rolls 61 and 72 in such a manner that the surfaces of the belts 63 and 74, which are affixed to travel at like speeds and in a like direction.

In FIGURE 3 there is schematically illustrated a drive and bearing arrangement suited for the roll arrangement of FIGURE 1, generally designated by the reference numeral 100. The arrangement 100 comprises a frame 101. The frame 101 defines a pivotal support 102 which is in operative engagement with the support arm 103. A hearing 104 is rigidly alfixed to the frame 101 which provides support which rotatably carries the shaft such as the shaft 14 of the roll arrangement of FIGURE 1. A second bearing 105 is disposed generally adjacent the bearing 104 and rotatably supports the shaft 33 of the roll 31 of FIGURE 1. A transversely sliding bearing 106 is supported by the frame in an elongate transverse slot 107. The bearing 106 is tensioned toward the support 102 by means of the spring 108. The bearing 106 received the shaft 26 of the roll 25 of FIGURE 1. A similar bearing arrangement, not shown, is disposed under the support arm 103 and carries the shaft 43 of the roll 45. An outwardly tensioned bearing 110 is disposed generally adjacent the bearing 106 and remote from the bearing 104. The bearing 110 moves laterally in a slot 111 defined by the frame 101. The bearing 110 is outwardly tensioned by means of a spring 112. The bearing 110 carries the shaft 23 of the tensioning roll 22. A similar bearing 114 is disposed in a slot 115 defined by the frame 101. The bearing 114 is outwardly tensioned by means of the spring 116. The bearing 114 rotatably supports the shaft 41 of the roll 40 of FIGURE 1. A dispenser 78a of hardenable resinous material is supported from the frame 101 by means of the support 7901. A motor 90a is rigidly affixed to the frame and supports a pulley 91a which drives a belt 92a which is in operative engagement with a pulley 93a affixed to a shaft 13a. The pulley 94a is in operative engagement with a twisted belt 95a. The belt 95a engages a pulley 96a which is rigidly affixed to a shaft such as the shaft 32 of the roll arrangement of FIGURE 1.

In operation of the present invention, the dispensing head such as illustrated in the accompanying drawing is pivotally afiixed to a support arm such as the support arm 28 of FIGURE 2 of US. Patent 3,206,899. Power is applied to the motor such as the motor 90 or 90a. The forming belts are caused to travel. Hardenable, foamable material is dispensed into the channel, defined by the belts and a starter strip, on a floor or similar foundation. Speed of the motor and the rate of additional hardenable material is adjusted so that the hardenable material is hardened and foamed to a supporting foam mass when the forming belts travel past its place of deposition.

Beneficially the segments, such as the segments 20, 38, 67 or 77 advantageously are prepared from materials such as foam, rubber and other synthetic resinous materials such as foamed polyethylene; however, it is generally beneficial to utilize as a foam contacting surface, on such segments, a non-adhering material which beneficially is a poly-tetrafiuoroethylene, polychlorotrifluoroethylene, and the like. If desired, however, conventional mold release agents may be employed to treat such surfaces, however,

when mold release agents are so utilized, the tendency of deposited foam to adhere to each other is somewhat reduced. Advantageously, the forming belts such as the belts 16, 35, 63 and 76 are also faced with a nonadhering material such as polytetrafiuoroethylene and the like.

As is apparent from the foregoing specification, the present invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. For this reason, it is to be fully understood that all of the foregoing is intended to be merely illustrative and is not to be construed or interpreted as being restrictive or otherwise limiting of the present invention, excepting as it is set forth and defined in the hereto appended claims.

What is claimed is:

1. A foam depositing head for the spiral generation of walled structures, the foam depositing head comprising in cooperative combination a frame, the frame supporting a first pair of side rolls and a second pair of side rolls, the rolls rotatably mounted in generally parallel relationship to each other, a first forming belt having a first edge and a second edge, the first edge of the first forming belt defining a plurality of edge segments projecting outwardly therefrom and being in adjacent generally contiguous arrangement, the first edge of the first forming belt disposed generally adjacent the frame, the first forming belt passing over the first pair of side rolls, a second side forming belt passing over and being supported by the second set of side rolls, the second side forming belt having a first edge and a second edge, the second side belt having a first edge and a second edge, the first edge of the second forming belt having a plurality of outwardly extending generally contiguous segments, the first and second forming belts defining therebetween a channel having three sides and a first end and a second end, the first end and second ends of the channel being open, the first side being defined by the first forming belt, the second side being defined by the second forming belt and a third side defined by the segments of the first and second forming belts, means to rotate the first and second pairs of rolls and to move the adjacent surfaces of the first and second forming belts in a like direction and means to provide a foamable, hardenable composition to the channel defined by the belts.

2. The apparatus of claim 1 including in each of the belts, an inwardly tensioning roll rotating about an axis generally parallel to the side rolls within each of the belts adapted to maintain adjacent segments of the belts in contact with each other.

3. The apparatus of claim 2 including an outwardly tensioning roll disposed within each of the belts adapted to maintain the belt tension.

4. The apparatus of claim 1 wherein the means to provide foamable, hardenable composition is a mixing chamber and nozzle adapted to receive, mix and dispense liquids.

5. The apparatus of claim 1 wherein the segments have a generally rectangular configuration.

References Cited UNITED STATES PATENTS 2,339,892 1/1944 Urschel 25131 X 2,506,716 5/ 1950 Finnemore 25131 2,607,100 8/1952 Urschel 2513l 2,841,205 7/1958 Bird 18-4 X 2,877,530 3/1959 Winn 25-1 3,206,899 7/ 1965 Wright 26445 X WILLIAM J. STEPHENSON, Primary Examiner. 

1. A FOAM DEPOSITING HEAD FOR THE SPIRAL GENERATION OF WALLED STRUCTURES, THE FOAM DEPOSITING HEAD COMPRISING IN COOPERATIVE COMBINATION A FRAME, THE FRAME SUPPORTING A FIRST PAIR OF SIDE ROLLS AND A SECOND PAIR OF SIDE ROLLS, THE ROLLS ROTATABLY MOUNTED IN GENERALLY PARALLEL RELATIONSHIP TO EACH OTHER, A FIRST FORMING BELT HAVING A FIRST EDGE AND A SECOND EDGE, THE FIRST EDGE OF THE FIRST FORMING BELT DEFINING A PLURALITY OF EDGE SEGMENTS PROJECTING OUTWARDLY THEREFROM AND BEING IN ADJACENT GENERALLY CONTIGUOUS ARRANGEMENT, THE FIRST EDGE OF THE FIRST FORMING BELT DISPOSED GENERALLY ADJACENT THE FRAME, THE FIRST FORMING BELT PASSSING OVER THE FIRST PAIR OF SIDE ROLLS, A SECOND SIDE FORMING BELT PASSING OVER AND BEING SUPPORTED BY THE SECOND SET OF SIDE ROLLS, THE SECOND SIDE FORMING BELT HAVING A FIRST EDGE AND A SECOND EDGE, THE SECOND SIDE BELT HAVING A FIRST EDGE AND 